Aldehyde is a useful compound as a material used in a chemical reaction or a perfume material and is conventionally composed by a dehydrogenation reaction, an oxidation reaction or the like using alcohol as a raw material. Among those reactions, a dehydrogenation reaction is an endothermic reaction, whereas an oxidation reaction which is an exothermic reaction, and thermal control during the dehydrogenation reaction can be easily achieved. Therefore, a dehydrogenation reaction has been used for an aldehyde production method in many cases. An aldehyde production method using a dehydrogenation reaction include, for example, a method in which a suspension is reacted using a catalyst in a batch manner, a method in which a suspension is reacted continuously using a catalyst, a method in which a reaction solution is continuously supplied to a reaction field (fixed bed) in which a catalyst formed into a predetermined shape is filled, thereby leading to a reaction, and like method.
In a dehydrogenation reaction, ester which is a dimerized aldehyde as a by-product is generated as well as aldehyde which is aimed to obtain. To cope with this, various improvements have been made to techniques for suppressing the generation of such a by-product and thus highly selectively causing a reaction. For example, in Patent Reference 1, a production method in which a dehydrogenation reaction is performed in a liquid phase using a ruthenium complex catalyst to store generated aldehyde in a gas state is disclosed. Also, Patent Reference 2 discloses a method in which alcohol is dehydrogenated by a low pressure gas phase reaction at a fixed bed to highly selectively generate aldehyde.
Patent Reference 1: Japanese Laid-Open Publication No. 2004-10568
Patent Reference 2: Japanese Translation of PCT International Application No. 2004-501881